We intend to investigate mechanisms that underlie temporal processing of auditory stimuli in the tree frog Hyla regilla. Specifically, we will investigate processes that allow cells in the auditory midbrain of anurans to become tuned to a particular amplitude modulated rate. Anurans use amplitude modulation (AM) and frequency modulation (FM) to differentiate their calls, e.g. mate call vs. aggressive call. Since AM rate is the only parameter that is changed between calls in Hyla regilla, it provides an excellent system in which to investigate how the processing of this parameter occurs in isolation. We will use estracellular recording while presenting various acoustic stimuli designed to indentify the mechanisms underlying AM rate tuning.